May 1, 2014: According to Star magazine, the real reason that Robin and Paula split is that they had a menage with a girl . . and then Robin kep on f*cking her behind Paula’s back. They say that they got their “source” to pass a polygraph test.

Here is their report:

Rumors of cheating have dogged the 37-year-old for months, but Star can reveal that it was one ongoing affair that upset Paula so much, she could never forgive him — mainly because she had been involved with the “other woman” as well!

For about two years, the duo had been carrying on a consensual three-way relationship with a massage therapist (whom Star will refer to as “Jasmine”). Things took a disastrous turn for the worst last summer, though, when Paula caught Robin and Jasmine carrying on a separate affair behind her back.